The objectives of the proposed center are to carry out coordinated, fundamental and clinical studies on drug absorption, distribution, metabolism and excretion as well as on the relationship between these processes and pharmacologic activity in health and disease. Proposed studies will focus on the clinical pharmacokinetics of nitroglycerin, procainamide, quinidine, lidocaine, prednisone, theophylline, ethosuximide, chloramphenicol and gentamicin, among other drugs. Studies on animal models will be concerned with d-propoxyphene, warfarin, heparin, estradiol, bilirubin and several antibiotics, among other drugs. Other aspects of the proposed research will be oriented to the elucidation of more basic or general problems in pharmacokinetics including the role of plasma and tissue binding in drug disposition, the effect of renal failure on the systemic availability of orally administered drugs and the design of general pharmacokinetic guidance systems.